Calculate the density of helium, He, in grams per liter 21 degree C and 752 mmHg

Question

Calculate the density of helium, He, in grams per liter 21 degree C and 752 mmHg. The density of air under these conditions is 1.188 g/L. What is the difference in mass between 1 liter of air and 1 liter of helium? (This mass difference is equivalent to the buoyant, or lifting, of helium per liter.) The previous example demonstrates that the density, of tonal to its molecular weight. Bromine, whose molecular weight is oxygen, as therefore more than five times as dense as air. Figure 5.16 gas being poured into a beaker where it displaces the and fills the relation between density and molecular weight of a gas old use a measurement of gas density to determine its molecular

Explanation / Answer

Density --> mass / Volume

so

mass = mol/MW

PV = nRT

n/V = P/(RT)

D = P*MW/(RT)

D = 752 mm Hg * 4 g/mol /(62.2 mm Hg *(21+273 K))

D =0.16449 g/L

1 liter of ait vs. helium

the ony thing that changes is MW so

MW of He = 4 g/ml

MW of air = 29 g/mol

so

29/4 --> air's density is 7.25 greater than Heliums

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---